dm: Provide a function to scan child FDT nodes

At present only root nodes in the device tree are scanned for devices.
But some devices can have children. For example a SPI bus may have
several children for each of its chip selects.

Add a function which scans subnodes and binds devices for each one. This
can be used for the root node scan also, so change it.

A device can call this function in its bind() or probe() methods to bind
its children.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 38 insertions, 25 deletions

diff --git a/test/dm/test-fdt.c b/test/dm/test-fdt.c
index 7980a683b54..cd2c38995e9 100644
--- a/test/dm/test-fdt.c
+++ b/test/dm/test-fdt.c
@@ -91,37 +91,17 @@ UCLASS_DRIVER(testfdt) = {
 	.id		= UCLASS_TEST_FDT,
 };
 
-/* Test that FDT-based binding works correctly */
-static int dm_test_fdt(struct dm_test_state *dms)
+int dm_check_devices(struct dm_test_state *dms, int num_devices)
 {
-	const int num_drivers = 4;
 	struct udevice *dev;
-	struct uclass *uc;
 	int ret;
 	int i;
 
-	ret = dm_scan_fdt(gd->fdt_blob, false);
-	ut_assert(!ret);
-
-	ret = uclass_get(UCLASS_TEST_FDT, &uc);
-	ut_assert(!ret);
-
-	/* These are num_drivers compatible root-level device tree nodes */
-	ut_asserteq(num_drivers, list_count_items(&uc->dev_head));
-
-	/* Each should have no platdata / priv */
-	for (i = 0; i < num_drivers; i++) {
-		ret = uclass_find_device(UCLASS_TEST_FDT, i, &dev);
-		ut_assert(!ret);
-		ut_assert(!dev_get_priv(dev));
-		ut_assert(!dev->platdata);
-	}
-
 	/*
 	 * Now check that the ping adds are what we expect. This is using the
 	 * ping-add property in each node.
 	 */
-	for (i = 0; i < num_drivers; i++) {
+	for (i = 0; i < num_devices; i++) {
 		uint32_t base;
 
 		ret = uclass_get_device(UCLASS_TEST_FDT, i, &dev);
@@ -144,6 +124,37 @@ static int dm_test_fdt(struct dm_test_state *dms)
 
 	return 0;
 }
+
+/* Test that FDT-based binding works correctly */
+static int dm_test_fdt(struct dm_test_state *dms)
+{
+	const int num_devices = 4;
+	struct udevice *dev;
+	struct uclass *uc;
+	int ret;
+	int i;
+
+	ret = dm_scan_fdt(gd->fdt_blob, false);
+	ut_assert(!ret);
+
+	ret = uclass_get(UCLASS_TEST_FDT, &uc);
+	ut_assert(!ret);
+
+	/* These are num_devices compatible root-level device tree nodes */
+	ut_asserteq(num_devices, list_count_items(&uc->dev_head));
+
+	/* Each should have no platdata / priv */
+	for (i = 0; i < num_devices; i++) {
+		ret = uclass_find_device(UCLASS_TEST_FDT, i, &dev);
+		ut_assert(!ret);
+		ut_assert(!dev_get_priv(dev));
+		ut_assert(!dev->platdata);
+	}
+
+	ut_assertok(dm_check_devices(dms, num_devices));
+
+	return 0;
+}
 DM_TEST(dm_test_fdt, 0);
 
 static int dm_test_fdt_pre_reloc(struct dm_test_state *dms)
@@ -187,7 +198,10 @@ static int dm_test_fdt_uclass_seq(struct dm_test_state *dms)
 	ut_asserteq(-ENODEV, uclass_find_device_by_seq(UCLASS_TEST_FDT, 7,
 						       true, &dev));
 
-	/* Note that c-test is not probed since it is not a top-level node */
+	/*
+	 * Note that c-test nodes are not probed since it is not a top-level
+	 * node
+	 */
 	ut_assertok(uclass_get_device_by_seq(UCLASS_TEST_FDT, 3, &dev));
 	ut_asserteq_str("b-test", dev->name);
 
@@ -236,12 +250,11 @@ static int dm_test_fdt_offset(struct dm_test_state *dms)
 							    node, &dev));
 
 	/* This is not a top level node so should not be probed */
-	node = fdt_path_offset(blob, "/some-bus/c-test");
+	node = fdt_path_offset(blob, "/some-bus/c-test@5");
 	ut_assert(node > 0);
 	ut_asserteq(-ENODEV, uclass_get_device_by_of_offset(UCLASS_TEST_FDT,
 							    node, &dev));
 
 	return 0;
 }
-
 DM_TEST(dm_test_fdt_offset, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);